Regarding processes, could you open Firefox's built-in Task manager (Shift+Esc) and compare what you see there with the Windows Task Manager. If you change the Windows Task Manager to the Details view (I think it's that second-to-last icon on the left button bar), then the Process IDs should match with Firefox's list.

Sometimes the presence of extra processes could indicate hidden windows used by malware, so it's worth tracking this down.

Regarding Firefox closing, I'm not sure what causes that. Did it just start recently?

OK, I got the build in Task manger and Windows task manger details open. So am I looking at, but not know what I'm looking for.

Yes it started to auto close about a month ago.

I would start here:

(1) If you scan down the list of sites open in the Firefox Task Manager, do you see anything unexpected?

(2) Does the total count of processes in Firefox match the count in Windows?

Here a screenshot of what I am seeing.

Sorry, that isn't the Firefox list I was expecting. Could you type or paste about:processes in the address bar and press Enter to load it?

Sorry my bad.

Okay, I see 16 processes there.

If you continue scrolling down, can you account for the others or are there many more in the Windows Task Manager?

Does Firefox's list include any unexpected sites that don't relate to the pages you have open?

Just in case there is an off-screen window with additional tabs, you can check the Firefox View > Open Tabs panel to find/close those extra tabs. You can access that using the file drawer icon at the left end of the Tab bar, or if you removed that, type or paste about:firefoxview in the address bar and press Enter to load it.

OK, here is the opened tabs and they all correct (also the open windows count)

It sounds like you are seeing normal Firefox per-site process isolation, but does the number make sense. There look to be eight sites open across your tabs, plus internal pages. Firefox creates processes for embedded content from other sites, like ads, so maybe that might get up to thirty or forty? 64 still seems high.

On the about:processes page, you can get an automated count of the number of processes by running a line of script in the web console --

While viewing the page, press Ctrl+Shift+K to open the console.

Type or paste the following into the console and either click "Run" (if that appears above the code) or press Enter to submit it.

document.querySelectorAll('tbody tr.process').length;

The first time you paste into the Web Console, Firefox may ask you to first type some characters to verify that you understand it is dangerous to run scripts from strangers. THAT IS TRUE. So let me explain what that snippet of code does:

Every line you see that is bold and has a process ID in parentheses is an HTML table row that is assigned class="process" so that it can be styled that way. The HTML looks like this:

<tr class="process">

document.querySelectorAll() is a function to build a node list of all the elements in the page that match a specific set of HTML tags and/or style rules.

The .length property is a count of items on the list. (If you leave this off, Firefox will show the actual list.)

So in your case, you would expect 64, or whatever number the Windows Task Manager currently shows. If it doesn't match, then we would suspect that there's another instance of Firefox running on the system.